In a world hungry for clean energy, engineers have created a new material that converts simple mechanical vibrations all around us into electricity to power sensors in everything from pacemakers to spacecraft.
The first of its kind and the product of decades of work by researchers at the University of Waterloo and the University of Toronto, the new generating system is compact, reliable, cheap and very, very green to generate electricity.
“Our breakthrough will have a significant social and economic impact by reducing our dependence on non-renewable energy sources,” said Asif Khan, a Waterloo researcher and co-author of a new study on the project. “We need these energy-generating materials more critically now than at any other time in history.”
The system that Khan and his colleagues developed is based on the piezoelectric phenomenon, which generates an electric current by applying pressure such as mechanical vibration to a suitable substance to generate electricity.
This effect was discovered in 1880, and since then a limited number of piezoelectric materials such as quartz and Rochelle salts have been used in technologies ranging from sonar and ultrasound imaging to microwave devices.
The problem is that until now, traditional piezoelectric materials used in commercial devices have had a limited capacity to generate electricity. They also often use lead, which Khan describes as “harmful to the environment and human health”.
Scientists have solved both problems to generate electricity
They began by growing a large single crystal of a molecular metal halide compound called edabco copper chloride using the Jahn-Teller effect, a well-known chemical concept related to the spontaneous geometric distortion of a crystal field.
Khan said the highly piezoelectric material was then used to produce nanogenerators “with record power density that can harvest minute mechanical vibrations under any dynamic circumstance, from human motion to automotive vehicles,” in a process that requires neither lead nor non-renewable energy.
The nanogenerator is tiny 2.5 centimeters square and about the thickness of a business card and could be conveniently used in countless situations. It has the potential to power sensors in a wide range of electronic devices, including the billions needed for the Internet of Things – a growing global network of objects with embedded sensors and software that connect and exchange data with other devices to generate electricity.
Dr. Dayan Ban, a researcher at the Waterloo Institute for Nanotechnology, said that in the future, a plane’s vibrations could power its sensory monitoring systems, or a person’s heartbeat could keep their battery-less pacemaker going.
“Our new material demonstrated record performance,” said Ban, a professor of electrical and computer engineering. “It represents a new way forward in this area.”
Written by: Vaishali verma